Five years ago, the leader of Hamas in Gaza, Yahya Sinwar, scrawled a note on a document that he knew Egyptian intermediaries would hand to Israeli Prime Minister Benjamin Netanyahu. Take a "'calculated risk' on a ceasefire," Sinwar wrote in Hebrew, according to former National Security Adviser Meir Ben-Shabbat.
Not long before, the Hamas chief had said something similar to an Italian journalist: "I don't want war anymore. I want a ceasefire." His ambition for the impoverished Palestinian coastal strip? "We can be like Singapore, like Dubai."
In the wake of Hamas's long-planned and brutal Oct. 7 assault on Israel, the Israeli security establishment is looking back on his words in a new light: as part of an effort to create the illusion that Hamas, considered a terrorist group by the US and European Union, was limiting its embrace of violence to focus on governance.
Israeli officials now acknowledge that a sense of complacency had set in around Hamas. In recent years, the military had greatly reduced its surveillance of the Gaza border fence, relying on electronic sensors and transferring troops out of the area to guard settlements in the West Bank.
As Israeli analyst Chen Artzi Sror wrote recently in the Yedioth Ahronoth newspaper, ambitious military intelligence analysts preferred to focus on Iran and Syria because working on Palestinian issues was not considered of existential importance.
The overarching sentiment was that Hamas had been deterred, and that the real challenges lay further afield.
"Sinwar read the Israeli consciousness very well," said Michael Milshtein, former head of Palestinian research for the military's intelligence department. "He wanted Israel to believe that Hamas was concentrating on stability in Gaza, promoting civil affairs. He planted this wrong idea in the minds of Israelis."
Today, as the Israeli military reduces much of Gaza to rubble in its mission to destroy Hamas, killing more than 11,000 people in the process, according to the Hamas-run health ministry, Sinwar is emerging as the assault's mastermind. He's the top target for assassination, assumed to be hiding deep in a Gaza tunnel, "like a little Hitler in a bunker," as Netanyahu put it recently.
As the Oct. 7 attacks remake regional - even global - politics, raising a risk of broader war, it's notable that the dynamic that gave rise to it is one of intimate enemies. Sinwar and the Israelis have been watching and analyzing one another for decades.
Born in a poor neighborhood of the southern Gaza town of Khan Younis, Sinwar, 61, helped found Hamas's military wing in the late 1980s as the first Palestinian uprising was underway. He later took on the task of rooting out Palestinian collaborators with Israel, and was responsible for killing four of them. Israeli military authorities, at the time still operating inside Gaza, sentenced him to life in prison in 1989.
Behind bars, Sinwar achieved deep fluency in Hebrew and Israeli society, regularly reading newspapers along with the biographies of key Israeli figures. He also became the uncontested leader of Hamas prisoners. According to Israeli officials and a former Hamas activist, while in prison he continued to have collaborators killed - including one he personally beheaded.
Officials describe him as a cold-blooded, magnetic leader; a compact, sinewy man whose close-cropped hair and beard have by now mostly turned white.
In the early 2000s, while in prison, Sinwar began experiencing headaches and blurred vision. He was taken to the Soroka Medical Center in Beersheba where a surgeon removed a brain tumor, saving his life.
Betty Lahat, the prison system's intelligence chief at the time, said in a TV documentary that she tried to use that event to recruit him as an agent.
"I said, the state of Israel saved your life," she said. "I thought I could turn him into one of ours, but he wasn't interested. He kept talking about the day he would be released. I told him you're never getting out. He said there's a date: God knows it."
There was a date. It was Oct. 18, 2011, when Israel exchanged more than 1,000 Palestinian prisoners for an Israeli soldier held by Hamas, Gilad Shalit. Among those released - and the man who drew up the list - was Sinwar.
Because he'd killed fellow Palestinians and not Israelis, and was no longer young, some Israeli officials didn't object to his being on the list. Others did.
"There was talk of how he was not a threat," recalled Milshtein, the former intelligence officer. "He doesn't want to return to dangerous activity, he's forgotten how to plan a terror attack. I tried to tell them they were wrong. Hamas is a mission for your whole life. It took him only a week to return to his connections and activities. Today, Hamas in Gaza is Sinwar."
He rejoined Hamas at a senior level and by 2017 had been elected the group's leader for all of Gaza, replacing Ismail Haniyeh, who was sent to Qatar.
"Hamas and Sinwar misled Israel and made it think war wasn't an option for Hamas," Akram Atallah, a Gaza-based columnist for the West Bank newspaper Al Ayyam, said by phone. "It was a sophisticated misinformation campaign deceiving Israel into believing they were seeking peace, workers, and economic life for Gaza residents."
After the October attack, a senior Hamas official, Ali Baraka, told the Russian state channel RT something similar - that the group had prepared for Oct. 7 for two years while fooling Israel into thinking it was "busy governing Gaza." Planning encompassed not only the attack, but also how Hamas would rule in its aftermath.
That was the subject of a 2021 conference in Gaza entitled "The Promise of the End of Days," where Sinwar delivered the keynote address. A summary document revealed it to have dealt with the topic of what to do with Israeli experts once the country was defeated: "Keep the Jewish scientists and experts in the fields of medicine, engineering, technology, civil and military industry for a while and do not let them leave with their knowledge and experience."
While Hamas officials never spoke directly to Israeli authorities, Sinwar worked through intermediaries to persuade Israel of his group's benign intentions. As part of these efforts, he collaborated with the Palestinian Authority to negotiate Israeli work permits for some 18,000 Gazans, allowing them to work as day laborers within Israel.
It was some of these workers who Israeli security officials say drew maps of the communities and made lists of local families to orient the Hamas militants before Oct. 7.
Since the attacks, Sinwar has not issued any statements or spoken to the press.
Meanwhile, 75 miles away from where the attacks took place, a poster hangs on the wall of the defense ministry in Tel Aviv. It features dozens of Hamas commanders with lines drawn across the faces of those who have been killed. The plan is to fill the poster with marks.
Sinwar is at the top.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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